Seroepidemiology of hepatitis A virus infection among schoolchildren in Taiwan

Abstract

Taiwan was a hyperendemic area for hepatitis A virus (HAV) infection before 1980. The aim of this study was to examine the association between seropositivity of antibodies against HAV (anti-HAV) by a community-based survey. School children from 10 elementary and 3 junior high schools, as well as staff members who worked at the above schools in central Taiwan were selected at random in this study. Anti-HAV was tested in sera of 1,954 healthy schoolchildren (aged 7-15 years old) and 254 teachers by enzyme-linked immunosorbent assay. Schoolchildren had a low prevalence of anti-HAV (2.3%) in contrast to the high seroprevalence in their teachers (52%). The seropositive rates of HAV antibody among the study subjects were increasing with age. No significant differences of anti-HAV seroprevalence among the study subjects were observed when they were stratified by gender, geographical area, household members, and parental education. Whereas, the anti-HAV seroprevalence was significantly higher in schoolchildren who were either aboriginal or living in areas without a supply of drinking tap-water. The seroprevalence of HAV data among the healthy pediatric population would be helpful to evaluate the need for mass vaccination policies.

Seroprevalence of <i>Helicobacter pylori</i> and Hepatitis A Virus among Children in Rural Central Taiwan

“…The prevalence of anti-HAV antibodies (0.96z; 2/209 patients) in patients born between 1984 and 1985 was shown to be due to natural HAV infection, while the 0.6z (1/168 patients) prevalence in patients born between 1993 and 1994 was due to HAV vaccination (37). Additionally, children aged 7-15 years had a significantly lower prevalence of anti-HAV antibodies compared to teachers in central Taiwan, and anti-HAV seroprevalence was higher among children living in rural and aboriginal areas compared to that among those living in urban areas (35). These study findings were consistent with other reports that HAV seropositivity in Taiwan has significantly declined following improvement of socioeconomic status (29,38,39).…”

“…H. pylori seropositivity was not associated with the number of siblings, parent educational levels, or family income (32); with gender, ethnicity, socioeconomic level, or source of drinking water (33); with family history of peptic ulcer or gastritis, or family member travel to other countries (28); or with region (34). HAV seropositivity was not associated with gender, ethnicity, parental education (35); with source of water supply, family member travel to other countries, or family history of alcohol or smoking (28); or with region and urbanization level (10,36).…”

Hepatitis A in Developed Country, the Result Should Interpret Carefully

“…The decreasing tendency of seropositivity of hepatitis A virus (HAV) in young healthy Korean adults was observed in our study1 and this epidemiological shift was shown in changing the developing countries to developed countries 2-4. The point that we suggest was the catch-up vaccination for young adults especially 20s who have only 6.2% of HAV seropositivity because they are vulnerable to severe symptomatic infection.…”

Clinical characteristics of acute hepatitis A outbreak in Taiwan, 2015–2016: observations from a tertiary medical center

“…Their study may explain why several outbreaks occurred at such frequency among the MSM population or HIV-infected patients, which restates the vulnerability of this population to acute hepatitis A [2–5]. In Taiwan, the low levels of immunity in the young population created the fundamentals for the hepatitis A outbreak, where the seroprevalence of anti-HAV is less than 10% in the general population [10, 15, 16]. We examined acute hepatitis A in 207 patients who received contemporary standard-of-care treatment.…”

“…Since June 1995, when efforts in public health and the free vaccination program for children in 30 indigenous townships were initiated, annual hepatitis A cases have declined from 2.96/100,000 in 1995 to 0.9/100,000 in 2003–2008 [9]. Since then, acute hepatitis A has become a disease mainly related to international travel, and the estimated seroprevalence against hepatitis A has decreased to less than 10% in those under the age of 20 according to the 2011 epidemiologic surveillance [10]. This population is particularly vulnerable to an acute hepatitis A outbreak.…”